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<p><b><span style="font-size:22pt">Explaination 031: &nbsp;</span></b></p>

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	<p>
	Sub-query in this answer will return one row value, concatenated first and last name for the employee with ID 180, so update will be successful. When sub-queries are linked to the parent by equality comparisons, the parent query expects only one row of data from the subquery. <br>
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	<p>
	  Incorrect Answers <br>
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	<p>
	  B: Sub-query will return concatenated first and last name for ALL records from the table EMPLOYEES. It will cause an error for the parent query, because it expects one only one row. <br>
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	<p>
	  C: Last WHERE statement in this query will generate error because sub-query returns multirow result. <br>
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	  D: SELECT statement for the NEW_EMPLOYEES table in this query will generate error because sub-query returns multi-row result. <br>
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	<p>
	  OCP Introduction to Oracle 9i: SQL Exam Guide, Jason Couchman, p. 150-156 <br>
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	<p>
	  Chapter 4: Subqueries
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